氨基酸分析仪检测牛乳中掺入的大豆蛋白

利用氨基酸分析仪对牛乳和大豆分离蛋白中的17 种氨基酸进行分离测定，氨基酸浓度在0.025～0.350 μmol/mL时，其峰面积和氨基酸浓度的线性相关系数均不小于0.988，重复性较好，牛乳加标回收率范围在94.2%～103.1%，相对标准偏差在0.89%～3.31%。通过对比分析牛乳和大豆的氨基酸图谱找到含量差异较大的6 种氨基酸，并根据模拟掺假实验样品的氨基酸分析6 种氨基酸含量和掺假量的线性关系，相关系数R2达0.889，建立牛乳中大豆蛋白掺假的定性定量检测方法。

Detection of Soybean Protein in Adulterated Milk by Amino Acid Analyzer

The separation and analysis of 17 amino acids in milk protein and soybean protein were conducted by amino acid
analyzer. When the concentrations of amino acids were in the range of 0.025–0.350 μmol/mL, the correlation coefficients
between peak areas and amino acid concentrations were above 0.988, the calibration curves of 17 amino acids all exhibited
good linearity and repeatability. Mean recovery rates and relative standard derivations (RSDs) for 17 amino acids from
spiked samples were in the ranges of 94.2% to 103.1%, and 0.89% to 3.31%, respectively. The linear relationship between
the contents of 6 selected amino acids showing significant differences in the amino acid profiles of the two proteins and the
amounts of added soybean protein was established by adulteration simulation experiments with correlation coefficients above 0.889.
This study has provided a good method for qualitative and quantitative detection of soybean protein adulterated milk.